Improvement in sewing-machines



Sheet 1.

2 Sheets Patented Decf, 1856.

L. JENNINGS.

Sewing Machine.

N. PETERSV Pnclolhugmpher. Washington. D. C.

2 Sheets--Sheet 2. L. JENNINGS.

Sewing Machine. No. 15,237. Famed Dec. 16, 1855.

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INTTED STATES PATENT Ormea.

LEVIS JENNINGS, OF `NIV YORK, N. Y.

IMPROVEMENT IN SEWING-MACHINES.

Specification forming part of Letters Patent No. 16,237, dated December 1G, 1856.

ing parts that are below the table A on which the work is performed. Fig. 3 is a vertical section at right angles to Fig. 1, showing a back view of the principal working parts of ythe machine. Fig. et is an inverted plan of the needle-bar and the stock of the bar. Fig. 5 is a side view of the stitching that is produced by the machine. Fig. G is a back view of what I call the thumb and finger,77 by which the loops are formed.

Similar letters of reference indicate corresponding parts in the several figures.

The principal feature of this invention consists in the employment of certain devices, hereinafter termed the thumb and iinger,77 in combination with a needle, whereby a seam is produced which differs from the seam produced in all other sewing-machines known to me. This seam is produced from a single thread, 'and partakes ofthe character of what is known as the chain stitchl seam, being formed by passing a series of loops through the cloth or other fabric and through each 'other in such a way as to be interloeked to prevent their being withdrawn; but instead of cach being received within and locking its immediate predecessor and receiving within it and being locked by its immediate sue` cessor, like the chain-stitch seam, each passes through its immediate successor and receives within it the second one succeeding it, as is illustrated in Fig. 5 of the drawings, where the thread is shown in gray color and the cloth in red. In this way a seam is produced which does not rip to such an extent when a stitch or. loop gives way as the chain-stitch seam before alluded to.

Io enable others skilled in the art to make and use my invention, I will proceed to describe its construction and operation.

A is the table or stand upon which the fabric is placed to be sewed, and B is a head-stock bolted thereto, for the purpose of carrying the upright needle-bar C, to which the needle a is attached. The needle-bar is operated by means of a lever, D, and a cam, E, in a substantially similar manner to the needle-bar of many other sewing-machines. The needle a is of the kind commonly employed, having an eye near its point. It has the same movement as the needles of most other sewing-machines, and it carries the thread through the fabric in a similar manner.

F is a small arm, of steel, working under the tablcA, and having formed at its extremity what I term the thumb and nger77 b c, by which, in connection with the needle, the loops are formed and interlocked. finger resemble almost exactly in their prole form the thumb and foreiinger of the human hand when parted and nearly straightened, the thumb being below the finger and slightly curved upward at its point, and the point of the finger being curved slightlydownward, and in the connection of the thumb and finger with the arm the resemblance to the prole of the human hand and wrist is continued, the wrist e being reduced in size, all of which is shown in Figs. 3 and 6 and part in Fig. l. The thumb and finger are made as thin as possible laterally, in order that they may pass easily between the needle and the thread that is protruded therewith through the fabric to form the loops passing close to the needle. The arm F is attached rigidly to the upper part of an upright pivot, f, which fits to turn freely in a bearing in the end of a horizontallymoving lever, G, which works on a fulcrum, g, on one side of the stand, and which is operated by the face, Lt, of the cam E, assisted by a spring, E. To the lower part of the pivotf is attached rigidly an arm, i, which is slotted to receive a fixed pin, j, which is attached to the stand ofthe machine. rlheslot in the arm c', being for the greater portion of its length described from thcfulcrum g of the lever G,serves, by working on the said fixed pin j, to keep the arm F in a fixed position relatively to the lever, the same as though it were rigidly attached thereto, during the greater portion ofthe lever s movement; but a sudden bend, if, in the slot (see Fig. 2) causes the pivot t-ov turn in the lever at one point in the movement of the'lat- This thumb and e y meer ter, and thus to give the thumb and finger a movement sidewise. In order that this move-` ment may be made sooner or later, the pin j is attached to a screw, j', which is adjustable nearer to or f'arther from the side of the stand A. lThe movement of the thumb and finger, while they occupy a fixed position relatively to the lever (l, serves to carry them between the needle and thread, to extend the thread and form the loops, and their lateral movement, which takes place after the needle has been withdrawn from the cloth, carries the loops under the needle, to enable it to pass through them in its descending movements. w is a fixed guide for the needle below the thumb.

Having described the movements of the lthumb and finger, Iwill proceed to describe the formation of the stitch.

At the time when the needle is passing through the fabric, which is represented in Figs. 3 and 6 in red outline, the thumb and finger are receding or moving toward the right hand of Fig. 3, completing their receding movement about the time the needle has completed its descent, and then remaining stationary while the needle rises to commence the formation of the loop, (see o, Fig. 3, where the thread is shown in blue colon) after which they advance into and through the loop o as far as their wrist c, in which condition they are shown in Fig. 3, the needle at the same time continuing to rise. Up to the time or nearly to the time of the needle leaving the cloth the arm F makes no movement. except its direct movement with the lever G, as the arc-formed portion of the slot il in the arm t' continues on the pin; but as soon as the needle leaves the cloth or has risen so high as to be out of the way of the finger and thumb, the arm is caused to move laterally by the bend i? in the slotted arm t' passing the pin j, and thus to-throw the finger and thumb under the needle before their advance terminates, and thereby to bring the loop o', (see Fig. 6,) whichwas formed by a preceding operation of the needle and has been since retained on the finger c and carried through the last loop, o, that has been formed in the cloth by the last descent and ascentof the needle, into a position for the needle to pass through it in its next descent, the opening` of this loop 0.to receive the needle being effected byaslight retreating movement of the arm F before the needle has descended far enough to enter vthe fabric. Then the point of the needle has passed through the fabric and entered into the loop o', as shown in Fig. 6, the arm Fmoves laterally away from the line of the needles motion I to make way for its continued descent, and

loop being retained on the wrist e, and pass through the one preceding it, thus, with a proper feeding movement of the fabric in the direction of the arrow shown in Fig. 6, producing the stitching or seam represented in Fig. In the formation of this seam by the above-described operation the first loop is caused to pass through the second loop and round the third,'the second to pass through the third and round the fourth, the third to pass through the fourth and round the fifth, and so on, every one passing through its immediate suecessor and receivi ng within it the second one that succeeds it.

In order to give the needle a very accurate movement, I fit the end of thelever I), which is operated upon by the cam E, with two frietion-rollers, l; and Z, the former of which is in tended torun on a hub, 7.1, of the cam and works on a pivot permanentlysecured to the lever, and the latter is intended to run on the outer side of the groove l, works on a pivot attached to the end of a short arm, m, which is attached to a pin or pivot, m', fitted to the lever. To the same pin or pivot m there is attached another arm, mi, of spring-steel,.

which rests against a setscrew, m?, which 'is held in a lug, m", on one side of the lever, and the elasticity of the arm serves to keep the roller YZ always close to the outside of the groove and the roller 7c to the inner side, notwithstanding'any wearing away of the cani or the roller, and thus prevents any shaking or uncertain movement of the lever D.

rlhe adiustment of the needle in proper relation to the thumb and finger is effected by fitting the needle-bar C to turn in a stock, H, with which the lever D connects, and by arranging the needle c eccentrieally to the needle-bar C, as is shown in Fig. 4t. By turning the needle-bar very slightly in its stock H the needle may be thrown backward or forward to make it work in close contact with or sufficiently near to the thumb and finger without being` sprung by or bearing too hardly against them. The bar is secured in the stock. in any desired position by means of a setscrew, n.

The feeding movement of the cloth is effect ed by two parallel rollers, Q q, grooved like ratchet-wheels, arranged to work in an open-l ing in the table Ar on two pivots, i' i', which are secured in a small stand, s, attached to the end of a horizontally-moving lever, I, which is arranged below the tableon a fulerum, t, and operated by two studs, u u, on the drivingshaft of the machine, assisted by a spring, u', in such a manner as to give the rollers a movement back and forth parallel with the table. These rollers only differ materially in their action from the feed-rollers of some other sewing-machines in being locked and unlocked in moving forth and back by means of dogs t o, having a positive movement, instead of by a common spring pawl or paWls, as generally used, and thereby insuring a more certain operation. The two dogs c" o are at the points ofthe two prongs of a strong forked piece, o, of metal, which is attached to.

a spring, wi?, secured on the top of the feed-lever I. This forked piece is provided with a hole, which worksonv the stem of the stand s as on a guide. Thertendeucy of the spring fw* is to hold down the dogs out of gear with the rollers; but during the advance of the thumb and linger to form the loop a Wedge, w, attached to the lever G, is caused by the movement of the said lever to pass between the le ver I and the spring fw* and lift it up, and thus to throw the dogs into gear with the rollers and lock them, and before the lever G moves back again and unlocks them the feeding movement of the lever I, which is sudden, takes place. The fabric is held in contact With the rollers by a foot-piece, y, such as is commonly employed for a similar use, acted upon by a spring, z.

I do not claim as my invention the belaying double-looped stitch described in the patent of 'W. I-I. Johnson, dated March 7, 1854; but

Vh at I claim as my invention, and desire to secure by Letters Patent, is-

1. rIhe formation of the seam from a single thread by passing each loop, after it has passed through the cloth or material to be seWed, through its immediate successor and round the second one which succeeds it by means of a lneedle and a thumb and finger, operating substantially as herein described.`

2. The combination of the arm F, to which the thumb and ringer b c are attached, the pivot f, the slotted arm fi, the fixed pin j, and the lever G,'or its equivalent, substantially as and for the purpose herein set forth.

L. J ENN IN GS. Ilfitnesses: i

WM. Tusorrn, Janus F. BUCKLE, Jr. 

